190 BRANNER 



ley at a place known as the Plasto de Godinho. Here the 

 drainage has cut through the sedimentary beds and exposed 

 beneath them a few small rounded bosses of the old under- 

 lying crystalline rocks. These are exposed over a distance 

 of only about one kilometer. The railway continues beyond 

 this over the Eocene (?) rocks. The top of the grade in passing 

 over the Serra dos Aymores is near kilometer 155.^ For several 

 kilometers along the watershed of the Serra dos Aymores there 

 are no rock exposures, and it is impossible to determine just 

 where the sedimentary rocks come to an end. At kilometer 

 160, however, the crystalline rocks appear in the bottom of a 

 gulch, and as boulders of sandstone are here mingled with blocks 

 of quartz-monzonite, it seems probable that this place is close to 

 the margin of the Eocene ( ?) sediments, and that the Serra dos 

 Aymores, where it is crossed by the railway, is capped by the 

 thin landward margin of these sediments. The country is 

 covered with a dense forest, and only occasional glimpses can 

 be had of the topography of the surrounding region. But these 

 glimpses are suggestive. At one point (kil. 145) one sees to the 

 right of the road an almost perpendicular and very sharp peak 

 rising high above the surrounding forests. At another point 

 another lofty peak is visible from the railway, also north of the 

 line. These mountains all have the same rounded and exfoli- 

 ated appearance so characteristic of peaks of crystalline rocks 

 in Brazil. 



The Serra dos Aymores is the northward extension of the Serra 

 do Mar along this part of the Brazilian coast. Seen from the ocean 

 it stands out boldly as a great mountain chain, extending from 

 about S. lat. 16° to about S. lat. 21° 30'. It is therefore a matter 

 of interest to find the railway crossing this serra upon horizontal 

 sediments. But the explanation seems to be that while these 

 Eocene (?) beds abut against the main range of the Serra dos 



' Unfortunately the elevations along the railway were not to be found when 

 I was at the Director's office. In the ^Mcinoria descriptoya sohre a estrada de 

 Ferro Bahia e Minas por M. de Teire e Ars^ollo,'' Rio de Janeiro, 18S3, I found 

 the elevations up to kilometer 13S, while the elevation of Theophilo Ottoni is 

 given in Hartt's book. Inasmuch as the road follows the river from where it 

 first reaches the Mucurj-, the profile is represented as even from that place to 

 Theophilo Ottoni. 



